1. Field of Invention
Aspects of this invention are related to color imaging, and are more particularly related to enhancing contrast in a color image.
2. Related Art
The da Vinci® Surgical System, commercialized by Intuitive Surgical, Inc., Sunnyvale, Calif., is a minimally invasive teleoperated surgical system that offers patients many benefits, such as reduced trauma to the body, faster recovery, and shorter hospital stay. One key component of the da Vinci® Surgical System is a capability to provide two-channel (i.e., left and right) video capture and display of visible images to provide stereoscopic viewing for the surgeon.
Such electronic stereoscopic imaging systems may output high definition video images to the surgeon. These systems also may allow features such as zoom to provide a “magnified” view that allows the surgeon to identify specific tissue types and characteristics, as well as to work with increased precision. In a typical surgical field image, however, certain tissue types are difficult to identify, or tissue of interest may be at least partially obscured by other tissue. Hence, various augmented modes of viewing have been developed in addition to the normal display mode. The surgeon typically switches back and forth between an augmented viewing mode and a normal display mode to see selected tissue with increased precision.
The augmented viewing modes are intended to assist the surgeon in differentiating structures in the image. One prior art augmented viewing mode uses a narrow band imaging system. This system utilizes narrow band spectrum illumination to highlight structures that are not easily seen under normal wide band visual spectrum illumination. The display for the narrow band images is typically pseudo colored by converting green and blue color components to three component colors. As a result, the surgeon needs to switch back and forth between the normal red-green-blue viewing mode and the narrow band viewing mode. See for example, M. Muto et al., “Narrow-band imaging of the gastrointestinal tract,” J. Gastenterology, Vol. 44 pp. 13-25 (2009). See also, K. Gono, “Multifunctional Endoscopic Imaging System for Support of Early Cancer Diagnosis,” IEEE Journal of Selected Topics in Quantum Electronics, Vol. 14, pp. 62-69 (2008).